Abstract:

With the development of intelligent transportation technologies, the exchange of information between vehicles has become increasingly frequent. Establishing an effective reputation management mechanism for the Internet of vehicles is important because it provides the foundation and guarantee for implementing various Internet of vehicles applications. This study proposes a hierarchical blockchain-based reputation management system to address issues such as the limited resources in the Internet of vehicles, low throughput of reputation management solutions, and poor recognition rates of malicious vehicles. The system considers the impact range of traffic data and designs a layered blockchain architecture to manage the data in a hierarchical manner, thereby achieving distributed storage of traffic data and reputation values and improving storage efficiency. By aggregating the credibility of messages and the reputation values of message source nodes, a Bayesian inference model is used to determine the authenticity of events. Using the Direct Acyclic Graph (DAG) blockchain structure to design reputation weight evaluation, the reputation value update algorithm is enriched and the management of reputation value is strengthened. Considering a scenario involving connected vehicles, the main node selection and consensus process of the traditional Practical Byzantine Fault Tolerance (PBFT) algorithm is improved, and an asset value based consensus committee selection strategy is proposed. Simulation results show that compared with existing schemes, the proposed method can effectively identifies false information and maintains a correct event judgment rate of over 91%, even when the proportion of malicious nodes reaches 30%. In terms of availability, transaction latency and throughput have significant advantages over the PBFT algorithm and some improved solutions, which can further expand the network scale. The proposed system is effective and feasible for the distributed trust management of the Internet of vehicles.

Key words: Internet of vehicles, blockchain, reputation management, consensus mechanism, consortium chain

摘要：

随着智能交通技术的发展，车辆间的信息交互趋于频繁。为车联网建立行之有效的信誉管理机制，是开展车联网多种应用的基础和重要保障。针对车联网资源受限、信誉管理方案吞吐量低、恶意车辆识别率差等问题，提出一种基于分层区块链的信誉管理系统。该系统考虑了交通数据的影响范围，设计的分层区块链架构对数据进行层次化管理，实现了交通数据和信誉值的分布式存储，提升了存储效率。通过聚合消息可信度和消息来源节点信誉值，使用贝叶斯推理模型完成对事件真实性判断。利用有向无环图(DAG)区块链结构设计信誉权值评价，丰富了信誉值更新算法，加强对信誉值的管理。面向车联网场景，改进传统实用拜占庭容错(PBFT)算法的主节点选取和共识过程，提出基于资产值的共识委员会选举策略。仿真实验结果表明，与现有方案相比，所提方案能够有效识别虚假信息，当恶意节点占比为30%时，仍能保持91%以上的事件正确判断率。在可用性方面，交易时延和吞吐量与PBFT算法及其部分改进方案相比，均有明显优势，能够进一步扩大网络规模。所提系统方案在车联网的分布式信任管理方面是有效可行的。

关键词: 车联网, 区块链, 信誉管理, 共识机制, 联盟链